US2810797A - Delay action switch - Google Patents

Description

Oct, 22, 1957 A. N GULNICK DELAY ACTION SWITCH 2 Sheets-Sheet 1 Filed April 11, 1955 INVENTOR ADR/O/V /V. GUZ/V/Ck ATTORNEY Oct. 22, 1957 A. N. GULNICK 1 DELAY ACTION SWITCH Filed April 11, 1955 2 Sheets-Sheet 2 INVENTOR AD/Q/OA/ /v. cum/c United States Patent 2,810,797 DELAY ACTION SWITCH 'A' drio'n N. 'Gulnick, Palisades Park, N. J., assignor to International Telephone and Telegraph Corporation, 'Nutley, N. J., a corporation of Maryland My invention relates to a delay action switch and is more particularly directed to the utilization thereof in connection with a generator of the type used to produce ringing current at a telephone subscribers set or to control the switching action of a relay or other spring pileup contact assemblies.

In generators of this type, it is usual to provide a switch to connect the generator to the line and to disconnect the telephone set, when a ringing signal is transmitted. Switches of this type, heretofore known, are actuated by centrifugal action and are relatively costly to manufacture and maintain. Furthermore it has been found undesirable to have the switching operation dependent upon the rotational speed of the generator.

An object of my invention is to provide a switching device having a delay characteristic which is relatively simple to construct and easy to maintain.

Anotherobject of my invention is to provide a generator switch which is actuated independent of the rotational speed of the generator.

One of the features of the invention is the provision of a suction cup device carried by a moving part of the switch. This cup is pressed into suction engagement with a given surface upon actuation of the switch at the instant I the drive shaft is turned. The switch remains in this act-uatedposition for a certain time after termination of the switch actuating force. The time delay may be adjusted according to requirements by a needle valve associated with suction cup.

Further objects and features of my invention will become more apparent by reference to the following description and the accompanying drawings, wherein:

Fig. 1 is an elevational view partially in section taken along the line 1--1 of Fig. 2 showing the switching device in a non-operated position;

Fig. 2 is plan view taken along the line 2-2 of Fig. 1 illustrating the switching device;

Fig. 3 is an elevational view partially in section taken along the line 11 of Fig. 2, with the switching device in operated position;

Fig. 4 is a view in perspective of the switching device;

Figs. '5 and 6 are schematic developments of a camclutch which actuates the switching device; and,

Fig. 7 is a sectional view of a valve used to control the delay required of the switch.

With reference to the drawings, the delayed action switch of my invention is illustrated in combination with a telephone ringing generator. The switch, for example, is shown mounted within a substantial cylindrical moisture-proof shell comprising housing elements 1, 2, and 3. The element 1 is an end closure adapted to be mounted on a panel 4 by a mounting nut 5. The housing element 2 is joined to the end element 3 by a retaining ring 6. The end element 3 contains the rotor and stator and the element 2 contains the drive mechanism, the detailed information of which may be had by reference to copending applications of O. C. From, L. B. Haigh and A. N. Gulnick, Serial No. 496,674, filed 2,810,797 Patented Oct. 22, 1957 March 25, 1955, and G. F. McCarthy and A. N. Gulnick, Serial No. 500,506, filed April 11, 1955, respectively.

A drive shaft 7 extends into the housing, from a drive handle 8. A cam-clutch device is mounted on the drive shaft 7 comprising a first part 9 carried by the shaft 7 and a second part 10 rotatably and axially moveable on the shaft. Parts 9' and 10 are biased against each other by restoring spring 11.

Figs. 5 and 6 illustrate a schematic development of the cam-clutch. Parts 9 and 10 are formed into annular elements having complementary U-shaped portions 12 and 13 and complementary V-shaped portions 14 and 15. The U shaped portions 12 are larger than portions 13 to provide a limited rotational movement during which the cam portions 14 and 15 cause the part 10 to move axially to actuate switching device 16, into an operated position shown in Fig. 3. The cam-clutch is returned upon termination of shaft movement to the normal position by the restoring spring 11 and the V shaped portions 14 and 15.

A transfer switch assembly 16, Fig. 4, comprises an arcuate frame 1601 which carries a spring leaf 17 having a make contact 17a, a spring leaf 18 having a break contact 18a and a transfer contact spring 19. The transfer spring 19 is equipped with a retarding device comprising a suction cup 20 having a needle valve 21 shown in enlarged detail in Fig. 7.

It may be seen from the above description that rotation of the drive shaft in either direction will move cam portion 10 axially into engagement with element 19a to actuate the transfer spring 19 to first open the break contact 18a, thereby disconnecting the substation circuits from the line, and next to close with make contact 17a, thereby connecting the generator output to the line. The cup 20 is also brought into suction engagement with the sealing plate 22.

Termination of the crank rotation permits the cam clutch to return to the normal non-actuating position, by means of the restoring spring 11 and the V-shaped portions 14 and 15. The suction cup 20, however, maintains the transfer spring 19 in the actuated position for a short interval of time, to permit the ringing voltage on the line to dissipate through the generator. The delay action of the switch may be adjusted according to requirements by the needle valve 21 contained in the suction cup 20. As shown in Fig. 7, the valve 21 is threadably received in valve body 23 onto which the resilient cup portion is secured. The threaded portion of the needle valve 21 has a groove 24 whereby a passageway is provided from between the interior and exterior of the cup, the passageway being controlled by the adjustment of the needle valve 21. After a predetermined time, depending upon adjustment of valve 21, the suction cup releases its grip on the surface 22 and the transfer spring 19 is restored to its normal position, thereby disconnecting the generator from the line and re-establishing the circuit for the telephone set by closing with break contact 13a. When the switch is in this normal position, the spacer 25 holds the leaf 17 and its contact 17a properly spaced from the transfer spring 19.

From the foregoing description it will be clear that I have provided an improved delayed action generator switch, having a delay action independent of the rotational speed of the generator. It will also be apparent that the switch structure is relatively easy to manufacture and to assemble with other parts of the generator and furthermore, that the delay action may easily be adjusted according to requirements.

While I have shown and described the switch in combination with a generator, it will be obvious to those skilled in the art that it may be applied to many switching devices where a delayed action is desired, either when the transfer spring is actuated or released. The suction cup may be used to control the contact operation of various relays and various spring assemblies. Still other applications are possible with contact pile-up assemblies actuated by means other than relays or rotating shafts.

While I have described above the principles of my invention in connection with specific apparatus, it is to be clearly understood that this descripion is made only by way of example and not as a limitation to the scope of my invention.

I claim:

1. In a telephone signalling generator having a drive shaft adapted to be rotated one or more times when a signalling current is desired, a transfer switch having break, make and transfer contacts, means responsive to initial rotation of said shaft to actuate said transfer contact to disengage said break contact and to engage said make contact, and to maintain the transfer contact in actuation throughout the rotation of said shaft, and retarding means operative upon termination of shaft movement to delay for a predetermined interval the return movement of said transfer contact.

in a telephone signalling generator having a drive shaft adapted to be rotated one or more times when a signalling current is desired, a transfer switch having break, make and transfer contacts, a cam device responsive to initial rotation of said shaft to actuate said transfer contact to disengage said break contact and to engage said make contact, and to maintain the transfer contact in actuation throughout the rotation of said shaft, and retarding means operative upon termination of shaft movement to delay for a predetermined interval the return movement of said transfer contact.

3. In a telephone signalling generator having a drive shaft adapted to be rotated one or more times when a signalling current is desired, a transfer switch having break, make and transfer contacts, means responsive to initial rotation of said shaft to actuate said transfer contact to disengage said break contact and to engage said make contact, and to maintain the transfer contact in actuation throughout the rotation of said shaft, and retarding means coupled to said transfer contact, said retarding means being operative upon termination of shaft movement to delay the return movement of said transfer contact, said retarding means being adjustable to selectively determine the delay interval.

4. In a telephone signalling generator having a drive shaft adapted to be rotated one or more times when a sig nalling current is desired, a transfer switch comprising a first element having a break contact, a second element having a make contact, a third element having transfer contacts disposed for co-action with said break and make contacts, a motion retarding device coupled to said third element adapted to be actuated into a retarding position by a movement of said third element, means responsive to initial rotation of said shaft to move said third element to effect disengagement of said transfer contacts with respect to said break contact and engagement with respect to said make contact and to cause said device to assume a retarding position, and to maintain the transfer contact in engagement with said make contact and said device in retarding position throughout the rotation of said shaft, said device operating to retard the return movement of said third element to effect a delayed switching action upon termination of shaft movement.

5. In a telephone signalling generator having a drive shaft adapted to be rotated one or more times when a signalling current is desired, a transfer switch comprising a first element having a break contact, a second element having a make contact, a third element of resilient character having transfer contacts disposed for co-action with said break and make contacts, the resilient character of said third element operating to normally bias said transfer andbreak contacts in engagement, a plate, a suction cup coupled to said third element adapted to be pressed into suction engagement with said plate, means responsive to initial rotation of said shaft to move said third element to effect disengagement with respect to said break contact and engagement with respect to said make con tact and to cause said suction cup to be pressed against said plate, and to maintain the third element engaged with respect to said make contact and said suction cup pressed against said plate throughout the rotation of said shaft.

6. In a telephone signalling generator having a drive shaft adapted to be rotated one or more times when a signalling current is desired, a transfer switch comprising a first element having a break contact, a second element having a make contact, a third element of spring material having transfer contacts disposed for co-action with said break and make contacts, said third element being disposed so that the resilience thereof normally biased the transfer contact thereof in engagement with said break contact, a suction cup coupled to said third element and adapted to be pressed into suction engagement with a given surface, means responsive to initial rotation of said shaft to move said third element to effect disengagement with respect to said break contact and engagement with respect to said make contact and to cause said suction cup to be pressed against said surface, and to maintain the third element engaged with respect to said make contact and said suction cup pressed against said plate throughout the rotation of said shaft, said suction cup having a passageway between the interior and exterior thereof and a valve adjustable to control the degree of opening of said passageway.

7. In a telephone signalling generator having a drive shaft adapted to be rotated one or more times when a signalling current is desired, a support, a first element having a break contact, a second element having a make contact, a third element having a transfer contact, said first, second and third elements being supported by said support with the contacts thereof disposed for coactive operation, said transfer and break contacts being normally biased toward engagement, a suction cup carried by said third element, means responsive to initial rotation of said shaft to move said third element for disengagement between said break and transfer contacts, for engagement between said transfer and make contacts and to press said suction cup against an adjacent surface to effect suction action, and to maintain the third element engaged with respect to said make contact and said suction cup pressed against said plate throughout the rotation of said shaft, whereby said suction cup retards the return of said third element to normal position upon termination of shaft movement.

References Cited in the file of this patent UNITED STATES PATENTS 2,313,064 Hall Mar. 9, 1943 2,394,712 Mudon Feb. 12, 1946 2,550,889 Tyler May 1, 1951 FOREIGN PATENTS 274,070 Switzerland June 16, 1951 768,719 France May 28, 1934

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